A prospective study to explore the role of serum lipoproteins in the development of recurrent stenosis after percutaneous transluminal coronary angioplasty was conducted on serum samples from 103 patients. Serum was collected at the time of angioplasty and evaluated for total cholesterol, total triglycerides (TG), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, very low-density lipoprotein cholesterol, and apolipoproteins A1 and B. In addition, LDL cholesterol/HDL cholesterol ratios and apolipoprotein B/A1 ratios were calculated for each sample. Information was then gathered from four years of follow-up after angioplasty, which was sufficient to establish the presence or absence of recurrent stenosis in 87 patients (68 males and 19 females). Stenosis recurred in 31 of the 87 patients (36%); the rate was similar for males (35%) and females (37%). Univariate analysis of the total patient population revealed no statistically significant difference in values for any of these lipoprotein parameters between success and recurrence groups. Likewise, multivariate analysis revealed no combination of lipoprotein values to be associated with success or recurrence. Findings were similar for the males alone and the total group of males and females. The female group was too small for separate statistical analysis. The power of this study to detect meaningful differences in each of these parameters except T G was at least 80%. These results do not support the hypothesis that lipoprotein factors influence the development of recurrent stenosis in patients undergoing coronary angioplasty.